Affordable
In terms of cost, there is no doubt they are more affordable than traditional homes (or even apartments) in Washington, DC. According to the U.S. Census Bureau's 2011 Washington, DC estimates, the median cost of rent is $1,216 per month. For over 60,000 renters that is 35 percent or more of their annual income going towards housing. Annual mortgage costs are even higher, with a annual median cost of $26,700.
If I were to order a tiny house blueprint from Tumbleweed Tiny House Company, the total cost of materials would be $23,000. That one time cost is more expensive than renting or buying a traditional house or apartment upfront, but in the long run is cheaper. Not to mention, if I were to move the house could come with me if it were mounted on a trailer.
Efficient
The efficiency of tiny houses is second to none. Matt Battin, a consulting architect at Boneyard Studios, compared designing a tiny house to a game of Tetris. It's all about finding the best way to fit in all the pieces of the home in the least amount of space as possible. These houses make the most of the space that they have. Tather than being built like a traditional home--with the intention of filling it with stuff once the shell is complete--tiny houses are built from the inside out. There is a consciousness of space and using that space effectively among tiny house builders that has become lost in the mainstream of our culture.
Green
Finally, these tiny houses are inherently green.